Background: Oxidative stress has been identified as a predisposing factor for dental caries. Saliva, as a rich source of antioxidants, plays an essential role in the protection against dental caries. Salivary enzymatic antioxidants include superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx).
Objectives: The aim of this study was to evaluate the correlation of salivary enzymatic antioxidant activity with different levels of dental caries in children.
Material and methods: In this cross-sectional study, 90 healthy children aged 7-12 years (36 girls, 54 boys) were investigated. Demographic information was gathered and dental examinations were provided for all participants. Then, unstimulated whole saliva samples were collected in the morning. The salivary SOD, CAT and GPx activity was measured spectrophotometrically. For statistical analysis, Spearman's correlation test, the Mann-Whitney U test and the Kruskal-Wallis test were used with the SPSS for Windows software, v. 16.
Results: Our results showed no significant correlation between SOD, CAT and GPx and the decayed, missing, filled teeth index for permanent/primary dentition (DMFT/dmft). The CAT activity was elevated in proportion to the number of decayed teeth. The SOD activity showed a positive correlation with the frequency of tooth brushing. The activity of SOD, CAT and GPx was higher in boys than in girls. An inverse relationship between enzymatic antioxidant activity and age was also observed.
Conclusions: Although enzymatic antioxidants had no positive correlation with DMFT/dmft, they were positively correlated with the number of decayed teeth and the improvement of oral hygiene.
Keywords: dental caries; enzymatic antioxidant; oral hygiene; saliva.